Section 5.6 Day 1 Graphing Inequalities in Two Variables Algebra 1

Learning Targets Graph linear inequalities on the coordinate plane A.REI.12 Graph the solutions to a linear inequality in two variables as a halfplane (excluding the boundary in the case of a strict inequality), and graph the solution set to a system of linear inequalities in two variables as the intersection of the corresponding half-planes. 5 Use appropriate tools strategically. Identify a linear inequality from a graph A.CED.3 Represent constraints by equations or inequalities, and by systems of equations and/or inequalities, and interpret solutions as viable or nonviable options in a modeling context.

Procedure 1. Solve for “y” 2. Graph the line <,> means a dotted line ≤,≥ mean a solid line 3. Select any test point that is NOT on the line. (You make this decision!) 4. Test the point you chose into the inequality 5. Shade the appropriate side Remember!

Example 1 Graph: 3𝑥−𝑦<2 1. Get “y” alone: 2. Graph the line: 3. Choose a test point: 4. Test the point: 5. Shade: Dotted (0,0) False! The other side!

Example 2 Graph: 𝑥+5𝑦≤10 1. Get “y” alone: 2. Graph the line: 3. Choose a test point: 4. Test the point: 5. Shade:

Example 3 Graph: 2𝑥+3𝑦≥18 1. Get “y” alone: 2. Graph the line: 3. Choose a test point: 4. Test the point: 5. Shade:

Example 4 Graph: 2𝑦−4𝑥>6 1. Get “y” alone: 2. Graph the line: 3. Choose a test point: 4. Test the point: 5. Shade:

Example 5 Write an inequality that represents the following graph: Y-intercept: Slope: Equation:

Example 6 Write an inequality that represents the following graph: Y-intercept: Slope: Equation:

Homework 5.6 Homework Worksheet Come to class with questions and prepare to practice this some more with an activity!

Post-It Round Robin Directions:   Roll the dice to choose which problem your group will complete. You will have 2 minutes to solve each problem individually. When the timer goes off, share your answers with the rest of your group. You will have until the music goes off to discuss and decide on one answer. Write your group name and answer on a post-it note and have one person stick it to the board under the correct question number. Repeat until all questions are answered!